With nothing more to lose and playing relaxed, the Filipino booters were able to contain the explosive Thais to two goals, disappointing the hometown crowd at the 700th Anniversary stadium who had been expecting a rout.
Aiding their cause was the ejection of tall striker Worrawot Srimaka in the 34th minute after elbowing half-back Alvin Ocampo as they jockeyed for position just in front of the goal area that reduced Thailand to 10 men.
It was the worthiest showing by far in recent memory by the Philippines against Thailand, the defending Southeast Asian Games champion and tipped to clinch the third edition of the regions premier soccer tourney.
"The 2-0 is a good result for us. We had nothing to lose, we felt no pressure. We were relaxed and it showed in the way we played today," said team manager Vince Santos.
"It was just too bad we were not able to take advantage of the fact Thailand was down to 10 men.